Carburetor



Jan. 5, 1932.

A. .1. GILBERT CARBURETOR Filed Aug. 4. 1927 Patented Jan. 5, 1932 UNITED STATES ALFRED J'. GILBERT, OF WINDSOR, CONNECTICUT CARBURETOR Application filed August 4, 1927. Serial No. 210,478.

My invention relates to .the class otdevices employed for mixing air with an inflammable material, as oil or other similar substance, for the purpose of aiding combustion, and an object of my invention, among oth-. ers, is the production of a device of this class that shall be simple inconstruction and particularly eflicient in operation.

One form of a carburetor embodying my in- 19 vention and in the construction and use of which the objects herein set out, as well as others, may be attained, is illustrated in the accompanying drawings, in which Tr Figure 1 is a front view of my improved carburetor.

Figure 2 is a view in section through the carburetor and illustrating its connection with a supply tank and to a vacuum producpg ing apparatus embodied in a system.

In the accompanying drawings the numeral 5 indicates the container of my improved carburetor that may be of any ordinary construction and form, preferably substantially round as to the main part when viewed from the top, and with a projection 4 terminating in a rib 6 on one side. A valve chamber 7 is contained Within the rib6 and an air inlet valve 8 seated on a spring 9 is located in the chamber 7 which chamber is closed at its top whichcover closes the entire top of the container. The chamber7 is separated from the main chamber 11 in the container by a wall 12 having an air inlet slot 13 communicating between the main and valve chambers, and the valve 8 serving to control an air inlet opening 14 through the cover 9, and through the slot 13.

An inlet chamber 15 is formed on the top of said cover and is closed by a cap 16. A fuel inlet 17 is formed in the wall of the chamber 15, a fuel supply pipe 18. being connected with said inlet and with a fuel supplyreservoir 19. A filtering chamber 20 is formed in the cap 16 with a filtering element 21, as a finely meshed wire, dividing said filtering chamber from the inlet chamber 15. A hold ing screw 22 extends through the chamber 20 into a hub 27 rising from the bottom of the chamber 15, and the cap 16 has struts 24 to by a projection at one edge of a cover 10,,

clamp the filtering element 21 against the end of said hub. The end of the screw 22 is formed as a valve seat for a valve passage 25 extending into the chamber 20 from an inlet valve chamber 26 formed in the hub 27 and having a port 28 extending into the chamber 11. I

A float valve 29 is located in the chamber 26, said alve being on a valve stem operated by a float 0 located in the chamber 11. An outlet valve body 31-extends into the bottom of the container 5 and to a point near the top of the chamber therein, this body being tubular and having a slot 32 extending partially around it and controlled'by a metering valve 33 located in said valve body and having a pin extending into said slot and a head 34 by means'of which the valve may be operated, said valve being arranged, as by cutting it away on oneside, to uncover more or less of the slot as may be desired to regulate the amount of fluid in the mixing chamber 35 located between the wall of the valve body 31 and an outlet tube 36 extending downwardly from the cover 10 into said valve body. Said outlet tube communicates with an outlet passage 37 to-Which a pipe 38 is connected, the other end of said pipe being connected with a pump 39 of any suitable form and construc tion adapted to cause flow of air and flui from the chamber 11 and to deliver said mixed air and fluid as through a pipe 40 to any suitable device, as a burner where such mixture is consumed.

The pump 39 may be drivenas by a motor 8 supplied with electricity through wires 41-42. This supply is controlled by a switch located on the cover 10, that is made use of to automatically stop the motor only when V abnormal conditions arise in the operation of the system.- Under ordinary conditions the running of the motor is controlled by any suitable device, as a thermostat 43 interposed in the electric circuit and operating in a manner that will be readily understood to affect the supply of fuel by the motor, and for which reason further and detailed description are omitted herein.

The switch is located in a box 44 secured to the outside of the wall of the chamber 15,

A switch blade 50 in the form of a flatspring attached at one end to blade supports 51, herein shown in the form of screws passing through one of the conductors 46, is adapted to have its opposite end pressed against a contact 52, likewise in the form of a screw extending through the other of said conductors and as shown in Figure 1 of the drawings.

" A switch blade actuator 54, in the form of a block of insulating material, is supported.

on an actuator support in the form of a rod slidably mounted in a post 56 projecting downwardly from the under sideof the cover 10 into the chamber 11, the lower end of said rod resting against the nose on the end of afloat lever 57 pivotally attached at one end to the post 56 and supporting the.

float 30 at its opposite end.

In the operation of the system under normal conditions the switch including the blade 50 will be normall closed and the operation will be regulated y the thermostat 43 that is connected as by a wire 58 with the motor, and by a wire 59 with the source of supply from which the wire 41 extends, the wire 41 being a positive and the wire 59 a negative wire. The chamber 11 is substantially air tight except for the opening 14 controlled by the valve 8. In the operation of the pump 39 to draw fuel from the chamber 11 a partial vacuum will be created in said chamber, and as soon as this is suflicient to permit atmospheric pressure to overcdme the tension of the spring 9, the valve 8 will open and admit air to the chamber 11 through the slot 13, and the tension of the spring 9 will be such as to restrict admission of air to produce a vacuum to suit the special conditions for which the carburetor is intended.

The partial vacuum produced within the chamber 11 will allow. the atmospheric pressure to force fuel from the supply tank 19 through the pipe 18 into the inlet chamber 15 from which it passes up through the filtering element 21 into the filtering chamber 20 and down through the valve passage 25 and port 28 into the chamber 11 where a substantially constant level is maintained by the action of the float 30 against the float valve 29 that opens to raise the level and closes when the proper level is reached. At the-beginning of the operation of the pump the fuel will be lowered in the mixing chamber 35 until the bottom end of the tube 36 is uncovered, when a mixture of air and fuel will be supplied to the pipe 38. The amount of fuelin this mixthe thermostat 43, or other equivalent device,

will operate to shut off the electric current and the operation of the pump will be stopped until the conditions are again overbalanced to a suflicient degree when the operation will be resumed.

Should the level of the liquid in the chamber 11 fall to or below a dangerous line, as by reason of some abnormal condition arising in the operation of the system, the nose on the lever 57, as the float lowers, will pass from under the end of the support 55 thereby releasing the actuator 54 which opens the switch and stops operation of the motor.

A small hole 60 is placed in the outlet tube 36 to prevent siphoning the fuel over into the pipe 38 when the device is not in operation. It will be evident that on the stoppage of operation with the column of fuel in the pipe 38 to a point below the fuel level in the chamber 5, there could be a continued flow down through the pipe, as in the case of the long leg of a siphon, but by the provision of the hole 60, air will enter the pipe, 38, at that point and thus break, or prevent any such action. However, when the pump is in action, though there will necessarily be some inflow of air through the hole, 60, the size of said hole is not so great relative to the I pump capacity as to hinder the flow of fuel along with such air, through the pipe, 36, and thence into the pipe, 38.

In accordance with the provisions of the patent statutes I have described the principles of operation of m invention, together with the device which I now consider to represent-the best embodiment thereof; but I desire to have it understood that the device shown is only illustrative and that the invention may be carried out by other means and applied to uses other than those above set out.

I claim- 1. A carburetor including a container arranged to permit a partial vacuum therein and having an air inlet opening, a valve to control flow of air through said opening, means for holding said valve in its closed position but to permit it to open under a predetermined vacuum, a float in said container, a supply pipe connected to the shell, an outlet from the container, and a valve operated by said float to control the flow from the supply, pipe to the container, motor-operated means to cause flow from said container, and means controlled by said float to stop the motor when the-fuel in the container is re-' duced to a predetermined extent.

'2. A carburetor including a container arranged to permit a partial vacuum therein and having an inlet opening, a valve completely closing said opening to control flow of air therethrough, means for controlling opening movement of the valve to create a -partial vacuum within the container suflicient to raise fuel from a lower level, a float in said container, a supply pipe connected to the container, an outlet from the container, a valve operated by said float to control flow from the supply pipe to the container, and means to cause flow of fuel from said container.

3. A carburetor including a container having an inlet opening, a tensioned valve completely closing said opening to control flow of air therethrough, a float in said container, a supply pipe connected to the container, an outlet from the container, a valve operated by said float to control flow from the supply pipe to the container, and means to cause flow of fuel from the container.

4. A carburetor including a container having an inlet opening, a valve completely closing said opening to control the flow of air therethrough, means for controlling opening movement of the valve to create a par tial vacuum within the container sufficient to raise fuel from a lower level, a float in said container, a supply pipe in communication with the container, an outlet from the container, a valve operated bysaid float thereby to control the flow from the supply pipe to the container, and means to cause flow from said container.

5. A carburetor as recited in claim 4, characterized by a fuel chamber above the container and the float operated valve controlling flow of fuel from the chamber to the container.

6. A carburetor as recited in claim 4, characterized by a fuel chamber above the container and the float operatedvalve controlling flow of fuel from the chamber to the container, and a filter interposed between the chamber and valve.

7. A carburetor including a container having an inlet opening, a tension-ed valve to control flow of air through said opening, a float in said container, a supply pipe connected to the container, an outlet from the container, means within the container for mixing fuel and air for delivery of said mixture from said container, a valve operated by said float to control flow from the supply pipe to the container, and means to cause flow of fuel from the container.

8. A device of the class described comprising a container having a liquid fuel chamber arranged to permit a partial vacuum therein, a fuel supply pipe connected to the chamber, a float-controlled valve controlling the flow of entering fuel through the supply pipe, a pump, an outlet pipe from said chamber connected to the pump and so related to the body of liquid fuel as to cause the pump to withdraw both air and liquid fuel from the chamber through the outlet pipe and thereby create a partial vacuum in said chamber, the latter having an inlet opening to admit air thereto, and a valve closing said opening, said valve being automatically controlled to provide arestricted admission of air to replenish air withdrawn by the pump but to maintain a partial vacuum in the chamber suflicient to raise fuel (through the supply pipe from a lower level.

9. A device of the class described comprising a container having a liquid fuel chamber arranged to permit a partial vacuum therein, a fuel supply pipe connected to the chamber, a float-controlled valve controlling the flow of entering fuel through the supply pipe,

said container having a compartmentseparated from the main fuel space of the 'container but communicating with the air space thereof, said compartment having a passage communicating with the main fuel space below the normal fuel level, means for controlling the flow of fuel from said fuel space to said chamber, a pump, an outlet pipe connected to the pump having a suction opening in said compartment to which the liquid fuel tends to flow under a gravity head, whereby the pump tends to withdraw both air and liquid fuel from the chamber through the outlet pipe and thereby create a partial vacuum-in said chamber, the latter having an inlet opening to admit air thereto, and a valve closing said opening, said valve being automatically controlled to provide a restricted admission of air to replenish air withdrawn by the pump but to maintain a partial vacuum in the chamber sufficient to raise fuel through the supply pipe from a lower. level.

10. A device of the class described comprising a container having a liquid fuel chamber arranged to permit a partial vacuum therein, a fuel supply pipe connected to the chamber, a float-controlled valve 'controlling the flow of entering fuel through the supply pipe, a pump, an outlet pipe from said chamber having a suction opening to which the liquid fuel tends to flow under a gravity head, a valve controlling the flow of fuel through said suction opening, said pump being connected to withdraw both air and liquid fuel from the chamber through the outlet pipe and thereby create a partial vacuum in said chamber, the latter having an inlet opening to admit air thereto, and a valve closing said opening, said valve being automatically controlled to provide a relower level.

11. A device of the class described comprising a container having a liquid fuel chamber arranged to permit a partial vacuum therein, a fuel supply pipe connected to i the chamber, a float-controlled valve controlling the flow of entering fuel through the supply pipe, a pump, an outlet pipe from said chamber having a suction opening to which the liquid fuel tends to flow under a gravity head, said pump being connected to withdraw both air and liquid fuel from thechamber through the outlet pipe and thereby create a partial vacuum in said chamber, the latter having an inlet opening to admit air thereto, and a valve closing said opening, said valve being automatically controlledto provide a restricted admission of air to, re-

plenish air withdrawn by the pump but to maintain a partial vacuum in the chamber suflicient to raise fuel through the supply pipe from a lower level.

.ALFRED J. GILBERT. 

